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#include "bits/stdc++.h"
using namespace std;
#define fi first
#define se second
#define ll long long
#define dbg(v) cerr<<#v<<" = "<<v<<'\n'
#define vi vector<int>
#define vl vector <ll>
#define pii pair<int,int>
#define mp make_pair
#define db long double
#define pb push_back
#define all(s) s.begin(),s.end()
template < class T > T smin(T &a,T b) {if (a > b) a = b;return a;}
template < class T > T smax(T &a,T b) {if (a < b) a = b;return a;}
const int N = (int)(2e5) + 5;
vector < pair < int , pii > > g[N];
multiset < pair < int , pii > > ss;
int was[N];
void add(int node)
{
was[node] = 1;
for (auto it : g[node])
if (ss.count(it))
ss.erase(ss.find(it));
else
ss.insert(it);
}
inline int readChar();
template <class T = int> inline T readInt();
template <class T> inline void writeInt( T x, char end = 0 );
inline void writeChar( int x );
inline void writeWord( const char *s );
/** Read */
static const int buf_size = 4096;
inline int getChar() {
static char buf[buf_size];
static int len = 0, pos = 0;
if (pos == len)
pos = 0, len = fread(buf, 1, buf_size, stdin);
if (pos == len)
return -1;
return buf[pos++];
}
inline int readChar() {
int c = getChar();
while (c <= 32)
c = getChar();
return c;
}
template <class T>
inline T readInt() {
int s = 1, c = readChar();
T x = 0;
if (c == '-')
s = -1, c = getChar();
while ('0' <= c && c <= '9')
x = x * 10 + c - '0', c = getChar();
return s == 1 ? x : -x;
}
/** Write */
static int write_pos = 0;
static char write_buf[buf_size];
inline void writeChar( int x ) {
if (write_pos == buf_size)
fwrite(write_buf, 1, buf_size, stdout), write_pos = 0;
write_buf[write_pos++] = x;
}
template <class T>
inline void writeInt( T x, char end ) {
if (x < 0)
writeChar('-'), x = -x;
char s[24];
int n = 0;
while (x || !n)
s[n++] = '0' + x % 10, x /= 10;
while (n--)
writeChar(s[n]);
if (end)
writeChar(end);
}
inline void writeWord( const char *s ) {
while (*s)
writeChar(*s++);
}
struct Flusher {
~Flusher() {
if (write_pos)
fwrite(write_buf, 1, write_pos, stdout), write_pos = 0;
}
} flusher;
int main(void)
{
freopen("apm.in","r",stdin);
freopen("apm.out","w",stdout);
int n,m;
n = readInt();
m = readInt();
while (m --)
{
int a,b,c;
a = readInt();
b = readInt();
c = readInt();
g[a].pb(mp(c,mp(a,b)));
g[b].pb(mp(c,mp(a,b)));
}
add(1);
ll answer = 0;
vector < pii > ans;
for (int i = 1;i < n;++i)
{
pii edge = ss.begin()->se;
int node = -1;
if (was[edge.fi])
node = edge.se;
else
node = edge.fi;
answer += ss.begin()->fi;
add(node);
ans.pb(edge);
}
writeInt(answer,'\n');
writeInt(n - 1,'\n');
for (auto it : ans)
writeInt(it.fi,' '),writeInt(it.se,'\n');
return 0;
}